This application is a 371 of PCT/FR98/02591 filed Dec. 2, 1998.
The present invention essentially relates to the use of diphenyldimethicone gum dissolved in a non-volatile silicone of the phenyltrimethicone type for preparing a cosmetic or pharmaceutical composition, notably dermatological composition, comprising a fatty phase.
In the state of the prior art, it is known from the document WO 97/12584 of silicone compositions as well as their method of preparation and their use in cosmetics for treating the skin or the hair.
Within the context of the prior art, these silicone gums are dissolved in a volatile silicone oil and are, for example, available on the market under the commercial denomination MIRASIL(copyright) C-DPDM, from RHONE-POULENC, France, i.e. a diphenyldimethicone, dissolved in cyclomethicone.
The silicone gums are particularly useful in cosmetics, since they bring about qualities which are essentially sought after in cosmetics such as smoothness, a slippery power, a shininess, a filmogenic character, an effect of resistance to water, a waterproof effect, an adherence effect, a conditioning effect, an anti-static effect, a softening effect conferring a soft feel, and a substantive effect, and a good hold with time.
A main aim of the invention is to provide a solution which enables facilitating the incorporation of silicone gum in cosmetic compositions or even pharmaceutical compositions, notably dermatological compositions, comprising a fatty phase.
A further main aim of the invention is to provide a solution which enables making an easy incorporation of a silicone gum in cosmetic or pharmaceutical compositions, notably dermatological compositions, by increasing the possibilities of formulation of these products with an upkeep or preferably an improvement of the compatibility with the other ingredients of the fatty phase and particularly the fatty bodies such as the oils by the waxes, in thus obtaining products of very good quality.
The present invention provides for the first time a solution to the whole of the technical problems set forth above in a particularly simple manner, which is inexpensive, which can be used on a cosmetically, pharmaceutically or notably dermatologically industrial scale.
Thus, according to a first aspect, the present invention relates to the use of a silicone gum of the diphenyldimethicone type dissolved in a non-volatile silicone oil of the phenyltrimethicone type for preparing a cosmetic or pharmaceutical composition, notably dermatological composition, comprising a fatty phase.
Within the context of the invention, the silicone gum of the diphenyldimethicone type has the following formula (I): 
in which x represents the number of recurring units which is generally not very high, preferably less than about 500, advantageously between about 50 and about 150, even better between about 80 and about 120, while y represents the number of recurring units which is generally higher, preferably at least equal to 1,000 and even better between about 1,000 and about 2,000.
Furthermore, within the context of the invention, non-volatile solubilising silicone oil of the silicone gum is a phenyltrimethicone of formula (II) below: 
in which x represents the number of recurring units which enables a viscosity to be obtained between about 10 and about 40 centistokes at a temperature of 25xc2x0 C. Preferably, x will have an average value of between 2 and 3.
Within the context of the invention, the relative proportion between the diphenyldimethicone silicone gum and the solubilising phenyltrimethicone silicone oil can vary within wide limits. However, this relative proportion will advantageously be between 0.1 to about 20% by weight of silicone gum, with respect to the mixture of silicone gum and solubilising phenyltrimethicone silicone oil, and even better between about 5 and about 15 by weight and ideally about 15% by weight.
However, according to other embodiments of the invention, the binary mixture of silicone gum of the dimethicone type and solubilising silicone oil of the phenyltrimethicone type will only constitute a part of the fatty phase, advantageously of 0.1 to 100%, better of 1% to 75%, even better 5 to 50% of the fatty phase.
Thus, within the context of the invention, the fatty phase can be constituted entirely of the binary mixture of the silicone gum mentioned above dissolved in the silicone oil of the phenyltrimethicone type.
This fatty phase will advantageously comprise at least one other silicone oil or non-silicone oil and optionally a fatty body which can advantageously be of plant origin.
At least one ester of glycerol and fatty acid in the form of a mono-, di- or tri-glyceride, an ester of acid and alcohol, the acid and/or alcohol being fatty, can be used as non-silicone oil, more generally a non-silicone fatty body.
Within the context of the present invention, i.e. of the description and the claims, the expression  less than  less than fatty acid greater than  greater than  is understood as meaning an acid having in general from 5 to 30 carbon atoms, having a linear or branched chain or even cyclic chain, which is saturated or unsaturated, which can comprise one or more aromatic rings, particularly one or more phenyl or benzyl groups.
Furthermore, within the context of the invention, i.e. of the description and the claims, it is also understood that the expression  less than  less than fatty alcohol greater than  greater than , means an alcohol having at least 8 carbon atoms, preferably between 8 and 30 carbon atoms.
Within the context of the invention, the fatty acid can also be used alone, having in this case a higher number of carbon atoms, particularly at least 12 carbon atoms, as defined above, and within the context of the use of a fatty alcohol alone, also having in this case at least 12 carbon atoms, as defined above.
Surfactant or emulsifying agents of the ionic or non-ionic type, such as sorbitan esters, polyoxyethylenated fatty alcohols, sucrose esters, can also be incorporated in the cosmetic or pharmaceutical compositions, notably dermatological compositions, of the invention.
According to an advantageous embodiment of the invention, the cosmetic or pharmaceutical compositions, notably dermatological compositions, can also contain at least one cosmetically or pharmaceutically acceptable additive, notably dermatologically acceptable additive, such as a thickening agent, a fatty acid ester particularly esters of fatty acid and glycerol, other volatile or non-volatile silicone oils, solar filters, plant oils, synthetic oils, perfumes, preservatives.
The compositions according to the invention can be formulated in various forms which are well known to the person skilled in the art, such as gel, milk, cream, lotion of variable consistency adapted to the uses sought after.
Within the context of the invention, the cosmetic or pharmaceutical compositions, notably dermatological compositions, will more particularly be used in the field of care of the skin, particularly of the face or of the body.
According to another variant, the cosmetic or pharmaceutical compositions, notably dermatological compositions, according to the invention, can be used for hair care.
According to a second aspect, the present invention also covers cosmetic, pharmaceutical compositions, notably dermatological compositions, characterised in that they comprise a fatty phase comprising a silicone gum of the diphenyldimethicone type dissolved in a non-volatile silicone oil of the phenyltrimethicone type, particularly as defined above.
According to an advantageous embodiment of the invention, this composition is a composition for the care of the skin and further comprises in the fatty phase a compound selected from the group consisting of:
an ester of glycerol, advantageously a triglyceride which is liquid at ambient temperature, such as glycerol tricaprylate/caprate, a caprylic/capric/succinic acid triglyceride, particularly at a concentration of about 1 to about 10% by weight,
a silicone oil of the phenyltrimethicone or dimethicone type particularly at a concentration between about 1 and about 10% by weight, better of the order of 2 to 5% by weight,
a plant oil, advantageously a jojoba oil or a meadowfoam seed oil, particularly at a concentration of 0.5 to 10% by weight, better of about 1 to about 5% by weight,
at least one gelling agent, advantageously a polysaccharide such as a xanthan gum or an acrylic polymer of the carbomer type, or a gelling mixture based on isoparaffin, polyacrylamide and polyoxyethylenated lauric alcohol, particularly commercially available under the commercial denomination of SEPIGEL 305 marketed by the company SEPPIC, particularly at a concentration between about 0.1 and about 10% by weight, better between about 0.1 and about 5% by weight,
an emulsifying/surfactant agent of the non-ionic type such as sorbitan stearate or a polyoxyethylenated sorbitan stearate or a sucrose ester such as sucrose stearate, particularly at a concentration between about 0.5 and about 5% by weight.
According to another embodiment of the invention, within the context of a composition intended for solar protection, this composition further comprises the following ingredients:
at least one chemical solar filter such as octyl methoxycinnamate, butylmethoxydibenzoylmethane, benzophenone-3 and benzophenone-4.
In the case of the use of octyl methoxycinnamate, a concentration between 0.1 and 10% by weight will in particular be used, in the case of butylmethoxydibenzoylmethane, a concentration advantageously between 0.1 and 5% by weight will be used, particularly of the order of 2 to 3% by weight, and for benzophenone-3 or -4, a concentration between 0.1 and 5% by weight will be used in particular,
at least one physical solar filter such as micronised titanium oxide particularly at a concentration between 0.1 and 20% by weight; micronised zinc oxide particularly at a concentration between 0.1 and 20% by weight, or any hybrid particles made from a mixture of titanium oxide or zinc oxide with another component particularly when these oxides are fixed on the surface of a polymeric particle, for example particles of polyethylene or of polypropylene comprising such oxides on their surface.
Such cosmetic, pharmaceutical compositions, notably dermatological compositions, can for example be constituted by hair compositions, in any form whatsoever, for example gel or cream, compositions intended for application on the skin, topically, in the form of an emulsion of the water-in-oil type or oil-in-water type, in the form of a gel, particularly a transparent gel, or even a lotion, or even anhydrous solid forms such as rods or sticks, or even products for the nails.
According to a second aspect, the present invention also relates to cosmetic or pharmaceutical compositions, notably dermatological compositions, comprising a fatty phase which itself comprises a mixture of silicone gum of the diphenyldimethicone type dissolved in a silicone oil of the phenyltrimethicone type, more particularly as defined above.
Naturally, these cosmetic or pharmaceutical compositions, notably dermatological compositions, can contain other active ingredients that the person skilled in the art will desire to incorporate, as well as various cosmetically, pharmaceutically, or dermatologically acceptable excipients or vehicles which are well-known to the person skilled in the art.
Other aims, characteristics and advantages of the invention will also appear clearly from the following description which is made in relation with various currently preferred preparation examples of the invention, which are given solely as an illustration and which will in no way limit the scope of the invention.